Chat server and client as a "bus"

Projects General Guidance
1

Hi everyone, I have been working on a project for a while now and have got it up and running thanks to the wealth of knowledge here :slight_smile: (thanks everyone for sharing all your experiences) I am at the point where i have made an android app that sends serial messages via Bluetooth to a arduino which takes the messages and controls a sainsmart relay board. Pretty simple serial communication type stuff. Now I am at the point where I want to expand. I am looking to create a network that will read messages much like a CAN bus but will not have the physical limitation that CAN has. My idea would be to have a arduino chat server (telnet) and arduino chat clients. A android app that will setup telnet automatically and when a button is pressed, send a message to the server. The Arduino's would read the telnet messages as a string and take action as needed. This would make it kind of like a chat bus? Anyway, the Arduino's would all be connected by ethernet so distance would not be an issue. So I guess the questions I have are:
Can you have multiple telnet clients connected at the same and all sharing the same session?
Would this method be a good way to provide communication between arduinos over ethernet?
Can anyone see a failure with this setup?

Thanks

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If you are going to have multiple clients, then a web based setup might be more practical.

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etherxrally:
Can you have multiple telnet clients connected at the same and all sharing the same session?

The Arduino network interfaces I've seen only support a small number of concurrent socket connections (four seems to be typical). You will need to check the library API you would be using to interface with your network interface to see what information it provides the server about the identity of the connected client. For example I've seen an Ethernet library that gave no information at all.

I don't know whether your application will need reliable comms i.e. to get positive confirmation of successful delivery of every message, but if it doesn't then UDP might be a more appropriate protocol to use - it would scale up much more easily.